> ## Documentation Index
> Fetch the complete documentation index at: https://developer.z-api.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Generate the SDK token

> Generates a session token to open the Connection SDK in the frontend

## Concept

This method generates a **session token** for the [Connection SDK](/en/partner/sdk-connector). Your backend calls this endpoint with your Client-Token and returns the resulting `token` to the frontend, which uses it in `ZAPIConnector.open({ token })`.

<Warning>
  This call must be made by **your backend**. Never expose your Client-Token or the instance credentials (instanceId and token) in the frontend. The generated token is short-lived — generate it on demand, right when the customer is about to connect.
</Warning>

Full implementation guide: [Connection SDK](/en/partner/sdk-connector).

***

## Attributes

### Header

<ParamField path="instanceId" type="string" required>
  Your instance ID. Available in the Z-API panel under **Instances**.
</ParamField>

<ParamField path="token" type="string" required>
  Your Z-API instance token.
</ParamField>

***

## Response

### 200

<ResponseField name="token" type="string">
  Session token to use in `ZAPIConnector.open({ token })` on the frontend
</ResponseField>

```json theme={"theme":{"light":"github-light","dark":"poimandres"}}
{
  "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..."
}
```

### 405

In this case, make sure you are sending the method specification correctly, i.e. check whether you sent POST or GET as specified at the beginning of this topic.

### 415

If you receive a 415 error, make sure to add the "Content-Type" of the object you are sending to the request headers — most often "application/json".